In the completion and production industry for natural resources, the formation of boreholes for the purpose of production or injection of fluid is common. The boreholes are used for exploration or extraction of natural resources such as hydrocarbons, oil, gas, water, and alternatively for CO2 sequestration.
Multilateral boreholes allow for a greater return on investment associated with drilling and completing simply because more discrete areas/volumes of a subterranean hydrocarbon deposit (or deposits) is/are reachable through a single well. Multilaterals generally require junctions at intersection points where lateral boreholes meet a primary borehole. Junctions are Y type constructions utilized to create flow paths at borehole intersections and are generally referred to as having a primary or main leg and a lateral leg.
For a multilateral junction installation procedure, the main bore section is typically completed first, followed by the lateral completion. These completions are known as lower completions as they refer to the portions of the borehole across the production (or sometimes injection) zones. The lower completions include some sort of perforations, screens, or the like to provide fluidic communication between the lower completion and the surrounding formation. Once the main bore and lateral sections are completed, the multilateral junction is installed, providing the flow paths at the intersection, or the junction can be installed simultaneously with the lateral section. The multilateral junction includes the main leg and lateral leg that are inserted in the main bore and lateral bore, respectively. An uphole portion of the multilateral junction is sized for connection to a liner hanger to anchor the junction to an outer casing. Subsequently, an upper completion is separately installed uphole of the multilateral junction on top of the liner hanger.
The art would be receptive to improved alternative devices and methods for completing a multilateral.